Stop 9 - Greater Wattenberg Area

Stop 9 - Greater Wattenberg Area, Energy Production & Environmental Impact

Figure 1. Salt Scar

Salt Scarring - In addition to studying oil and gas resources, we are also looking at the deleterious effects of past energy exploration and production. In this area, we are studying the relationship between waters produced during petroleum extraction, which are typically brines, and the formation of salt deposits on the surface. We specifically studied the site at Stop 9 to determine whether briny waters were leaking from storage tanks onto the surface and also then working their way into shallow aquifers. Preliminary results of our studies seem to be showing that formation of the salts, principally the sodium-sulfate mineral thenardite, may actually result from leaching of subcrops of coal-bearing units as a result of changes in shallow subsurface water flow due to irrigation and development rather than from leakage of produced waters (brines) from storage tanks.

Old Coal Mines - Another area where we are studying the deleterious effects of past energy extraction is in the Boulder-Weld Coal Field. Although coal is no longer produced in the region, many mines were dug at relatively shallow depths (50-500 ft) over the life of the Boulder-Weld Coal Field. We are compiling, in digital form, a map showing the distribution of coal mines and depth to mining in the Boulder-Weld Coal Field. This map, which will be used principally by the State in their geotechnical assessment of proposed future developments, is important to refer to particularly as development and urbanization proceeds in the rapidly expanding parts of Boulder County, an area that is largely underlain by relatively shallow subsurface coal mines. A similar effort is planned in the El Paso Coal Field, which underlies Colorado Springs.

Figure 2. Index map showing the Front Range Infrastructure Resources Project (FRIRP) demonstration area,
and the generalized extent of the Boulder-Weld coal field study area in Northwest Colorado.

U.S. Department of the Interior, U.S. Geological Survey
URL: http://rockyweb.cr.usgs.gov/frontrange/virtour/enviro.htm
Contact: Carol Mladinich mailto:csmladinich@usgs.gov
Updated: 05/16/2001